Two of the three prosecutors who stepped down this week from the case of a former BP engineer charged with obstructing the investigation of the 2010 Gulf of Mexico oil spill are leaving the Justice Department.

Acting Assistant Attorney General Mythili Raman of the Justice Department’s criminal division said in a statement Friday that Assistant U.S. Attorneys Derek Cohen and Avi Gesser are departing.

“As they leave the department, we wish them the very best in their careers,” Raman said.

Their future plans were not disclosed.

The third prosecutor who stepped down from the Kurt Mix case, Scott Cullen, is staying at the Justice Department, but had not been expected to participate in Mix’s trial, Justice spokesman Peter Carr said.

The agency earlier attributed the withdrawal of the three prosecutors from the case as a “staffing adjustment.”

Records list four other prosecutors as counsel of record on the Mix case, set for trial Dec. 2.

U.S. District Judge Stanwood R. Duval Jr. this week approved the request to allow Cohen, Gesser and Cullen to withdraw from the case.

Mix is accused of deleting text messages and voice mails about the amount of oil that was flowing into the Gulf after a BP well a mile beneath the sea blew out, triggering an explosion on the Transocean-owned Deepwater Horizon rig that killed 11 workers.

He has pleaded not guilty to two counts of obstruction of justice. Two BP well-site leaders and a former BP executive also face charges in connection with the disaster and are awaiting trial.